Hardware for split data translation lookaside buffers

ABSTRACT

Systems, methods, and apparatuses relating to hardware for split data translation lookaside buffers. In one embodiment, a processor includes a decode circuit to decode instructions into decoded instructions, an execution circuit to execute the decoded instructions, and a memory circuit comprising a load data translation lookaside buffer circuit and a store data translation lookaside buffer circuit separate and distinct from the load data translation lookaside buffer circuit, wherein the memory circuit sends a memory access request of the instructions to the load data translation lookaside buffer circuit when the memory access request is a load data request and to the store data translation lookaside buffer circuit when the memory access request is a store data request to determine a physical address for a virtual address of the memory access request.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present patent application claims the benefit of U.S. Provisional Patent Application No. 62/881,135, filed Jul. 31, 2019, and titled: “Hardware for Split Data Translation Lookaside Buffers”, which is incorporated herein by reference in its entirety.

BACKGROUND

A processor, or set of processors, executes instructions from an instruction set, e.g., the instruction set architecture (ISA). The instruction set is the part of the computer architecture related to programming, and generally includes the native data types, instructions, register architecture, addressing modes, memory architecture, interrupt and exception handling, and external input and output (I/O). It should be noted that the term instruction herein may refer to a macro-instruction, e.g., an instruction that is provided to the processor for execution, or to a micro-instruction, e.g., an instruction that results from a processor's decoder decoding macro-instructions.

BRIEF DESCRIPTION OF DRAWINGS

Various embodiments in accordance with the present disclosure will be described with reference to the drawings, in which:

FIG. 1 illustrates a processor core including a load data translation lookaside buffer circuit and a store data translation lookaside buffer circuit according to embodiments of the disclosure.

FIG. 2 illustrates a load data translation lookaside buffer circuit according to embodiments of the disclosure.

FIG. 3 illustrates a store data translation lookaside buffer circuit according to embodiments of the disclosure.

FIG. 4 illustrates a flow diagram for a load data request according to embodiments of the disclosure.

FIG. 5 illustrates a flow diagram for a store data request according to embodiments of the disclosure.

FIG. 6 illustrates a flow diagram according to embodiments of the disclosure.

FIG. 7A is a block diagram illustrating a generic vector friendly instruction format and class A instruction templates thereof according to embodiments of the disclosure.

FIG. 7B is a block diagram illustrating the generic vector friendly instruction format and class B instruction templates thereof according to embodiments of the disclosure.

FIG. 8A is a block diagram illustrating fields for the generic vector friendly instruction formats in FIGS. 7A and 7B according to embodiments of the disclosure.

FIG. 8B is a block diagram illustrating the fields of the specific vector friendly instruction format in FIG. 8A that make up a full opcode field according to one embodiment of the disclosure.

FIG. 8C is a block diagram illustrating the fields of the specific vector friendly instruction format in FIG. 8A that make up a register index field according to one embodiment of the disclosure.

FIG. 8D is a block diagram illustrating the fields of the specific vector friendly instruction format in FIG. 8A that make up the augmentation operation field 750 according to one embodiment of the disclosure.

FIG. 9 is a block diagram of a register architecture according to one embodiment of the disclosure

FIG. 10A is a block diagram illustrating both an exemplary in-order pipeline and an exemplary register renaming, out-of-order issue/execution pipeline according to embodiments of the disclosure.

FIG. 10B is a block diagram illustrating both an exemplary embodiment of an in-order architecture core and an exemplary register renaming, out-of-order issue/execution architecture core to be included in a processor according to embodiments of the disclosure.

FIG. 11A is a block diagram of a single processor core, along with its connection to the on-die interconnect network and with its local subset of the Level 2 (L2) cache, according to embodiments of the disclosure.

FIG. 11B is an expanded view of part of the processor core in FIG. 11A according to embodiments of the disclosure.

FIG. 12 is a block diagram of a processor that may have more than one core, may have an integrated memory controller, and may have integrated graphics according to embodiments of the disclosure.

FIG. 13 is a block diagram of a system in accordance with one embodiment of the present disclosure.

FIG. 14 is a block diagram of a more specific exemplary system in accordance with an embodiment of the present disclosure.

FIG. 15, shown is a block diagram of a second more specific exemplary system in accordance with an embodiment of the present disclosure.

FIG. 16, shown is a block diagram of a system on a chip (SoC) in accordance with an embodiment of the present disclosure.

FIG. 17 is a block diagram contrasting the use of a software instruction converter to convert binary instructions in a source instruction set to binary instructions in a target instruction set according to embodiments of the disclosure.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth. However, it is understood that embodiments of the disclosure may be practiced without these specific details. In other instances, well-known circuits, structures and techniques have not been shown in detail in order not to obscure the understanding of this description.

References in the specification to “one embodiment,” “an embodiment,” “an example embodiment,” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

A (e.g., hardware) processor (e.g., having one or more cores) may execute instructions to operate on data, for example, to perform arithmetic, logic, or other functions. A hardware processor may access data in a memory. In one embodiment, a hardware processor is a client requesting access to (e.g., load or store) data and the memory is a server containing the data. In one embodiment, a computer includes a hardware processor requesting access to (e.g., load or store) data and the memory is local to the computer. Memory may be divided into separate blocks (e.g., one or more cache lines) of data that may be managed as a unit for coherence purposes. In certain embodiments, a (e.g., data) pointer (e.g., an address) is a value that refers to (e.g., points to) the location of data, for example, a pointer may be an (e.g., linear) address and that data may be stored at that (e.g., linear) address. In certain embodiments, memory may be divided into multiple lines and each line may be have its own (unique) address. For example, a line of memory may include storage for 512 bits, 256 bits, 128 bits, 64 bits, 32 bits, 16 bits, or 8 bits of data. An address may be a virtual address or a physical address. A processor may convert a virtual address (e.g., as seen by a program running on the processor) to a physical address (e.g., the address in memory hardware).

In certain embodiments, a translation lookaside buffer (e.g., TLB) converts a virtual address to a physical address (e.g., of the system memory). A TLB may include a data table to store (e.g., recently used) virtual-to-physical memory address translations, e.g., such that the translation does not have to be performed on each virtual address present to obtain the physical memory address. If the virtual address entry is not in the TLB, a processor may perform a page walk to determine the virtual-to-physical memory address translation.

As processor core instructions per cycle (IPC) increases, load and store bandwidth increase accordingly in certain embodiments. A core may include a plurality of load data ports and a plurality of store data ports (e.g., of a memory circuit) that allow a plurality of load operations and a plurality of store operations to execute every cycle. In certain embodiments, a memory circuit (e.g., memory controller) is to perform virtual address (e.g., as input) to physical address (e.g., as output) translations by looking up the virtual address in a translation lookaside buffer (TLB).

In certain embodiments, a plurality of load data ports into memory and a plurality of store data ports into memory result in a data TLB structure that is also multi-ported. To overcome one or more negative effects by having a single data TLB with increasing area, complexity, and power, certain embodiments herein split a unified load and store DTLB into two independent (e.g., separate and distinct) structures: a load DTLB and a store DTLB. In certain embodiments, the load DTLB and store DTLB are different sizes, different associativity, are looked up by different operations, have different replacement and fill policies, or any combination thereof.

Certain embodiments herein utilize a load DTLB (e.g., circuit) and a store DTLB (e.g., circuit) that is separate and distinct from the load DTLB, for example, in contrast to using two TLBs (one for loads and one for stores) that are shadowed so it is actually two copies of the same structure, e.g., made to reduce a number of read ports. A shadowed TLBs solution may support TLBs with multiple read ports but at a cost of duplicating the area and power of the TLB structures. Certain embodiments herein utilize a load DTLB (e.g., circuit) and a store DTLB (e.g., circuit) that is separate and distinct from the load DTLB such that there is no maintaining current state (e.g., translations) as between two shadowed data TLBs (e.g., and thus no corresponding signaling back and forth as between two shadowed data TLBs).

Certain embodiments herein provide for a load DTLB (e.g., circuit) and a store DTLB (e.g., circuit) that is separate and distinct from the load DTLB to allow for scalability with a plurality of load ports and store ports. Certain embodiments herein provide for a load DTLB (e.g., circuit) and a store DTLB (e.g., circuit) that is separate and distinct from the load DTLB to serve multiple load and store ports without a cost of duplicating a unified (shadowed) DTLB structure for loads and stores. Certain embodiments herein provide for a load DTLB (e.g., circuit) and a store DTLB (e.g., circuit) that is separate and distinct from the load DTLB to logically separate the load DTLB for load operations and the store TLB for store operations, e.g., so the store DTLB and load DTLB can be built separately according to project needs and constraints. Certain embodiments herein provide for a load DTLB (e.g., circuit) and a store DTLB (e.g., circuit) that is separate and distinct from the load DTLB to allow different sizing (e.g., the number of entries storage locations in each) of load DTLB and store DTLB structures. For example, in certain embodiments store operations are less sensitive for DTLB size for performance and therefore a store DTLB can be made smaller and simpler in these embodiments, thus increasing power and area advantages.

In one embodiment, the decoding and execution of a CPUID instruction enumerates if the processor core includes a load DTLB and a store DTLB that is separate and distinct from the load DTLB.

In certain embodiments, the load DTLB is looked up only by load operations (e.g., and executed on a load port). In certain embodiments, the store DTLB is looked up only by store operations (e.g., and executed on a store port). In certain embodiments, a load DTLB is filled (e.g., mappings are updated) on every load operation and every store operation, for example, because the store to load forwarding may be used and therefore there may be a high probability that after a store will come a load (e.g., to the same page) and it may be desirable to have the load's address translation ready. In certain embodiments, the store DTLB is filled only by store operations, e.g., to cause the store DTLB to be (e.g., much) smaller that the load DTLB. In one embodiment, a load DTLB has 64 entry storage locations (e.g., for translations) and the store DTLB has 16 entry storage locations. In certain embodiments, a load DTLB is true performance critical and also cycle-time critical structure so it is placed in the centric area of the core, e.g., closer to the other units (e.g., circuits), for example, and features the full size with less read and write ports. In certain embodiments, a store DTLB is less sensitive for performance and is built as a side structure, e.g., with a smaller number of entries and less logical complexity.

FIG. 1 illustrates a processor core 100 including a load data translation lookaside buffer (TLB) circuit 172 and a store data translation lookaside buffer (TLB) circuit 173 according to embodiments of the disclosure. In certain embodiments, load data TLB circuit 172 is separate and distinct from store TLB circuit 173. In one embodiment, components of core (e.g., memory access circuit(s) 164) are coupled to one or more ports (e.g., 171) into load data TLB circuit 172 and/or to one or more ports (e.g., 175) into store data TLB circuit 173. In certain embodiments, a component(s) of core (e.g., memory access circuit(s) 164 or memory circuit 170) (e.g., orchestrator circuit 177) is to determine whether a memory access request is a load data request or a store data request, and steer load data requests to the load data TLB circuit 172 and steer store data requests to the store data TLB circuit 173. In certain embodiments, a load buffer and/or a store buffer are utilized in memory circuit 170 to store load data requests and store data requests, respectively, e.g., before being serviced by load data TLB circuit 172 or store TLB circuit 173. In certain embodiments, a memory access request is a load data request (or requests) sent (e.g., by orchestrator circuit 177) to load data TLB circuit 172, and the load data TLB circuit 172 searches its data structure to determine if a mapping of a virtual address for that load data request is present, and if so, the physical address corresponding to that virtual address is output and used to access the data-to-be-loaded, e.g., within data cache circuit 174 (e.g., L1 data cache). In certain embodiments, a memory access request is a store data request (or requests) sent (e.g., by orchestrator circuit 177) to store data TLB circuit 173, and the store data TLB circuit 173 searches its data structure to determine if a mapping of a virtual address for that store data request is present, and if so, the physical address corresponding to that virtual address is output and used to access the data-to-be-stored, e.g., within data cache circuit 174 (e.g., L1 data cache). In certain embodiments, memory circuit 170 (e.g., orchestrator circuit 177) performs a page walk for any miss in a TLB, e.g., to determine a physical address for a virtual address without using the TLB. In certain embodiments, each arrow between execution clusters 160 and load data TLB circuit 172 or store TLB circuit 173 is used to depict a plurality of discrete ports (e.g., and wires) to send a request to a respective port of parallel input ports of a TLB circuit.

Depicted processor core 100 includes a front end circuit 130 coupled to an execution engine circuit 150, and both are coupled to a memory circuit 170. The core 100 may be a reduced instruction set computing (RISC) core, a complex instruction set computing (CISC) core, a very long instruction word (VLIW) core, or a hybrid or alternative core type. As yet another option, the core 100 may be a special-purpose core, such as, for example, a network or communication core, compression engine, coprocessor core, general purpose computing graphics processing circuit (GPGPU) core, graphics core, or the like.

The front end circuit 130 includes a branch prediction circuit 132 coupled to an instruction cache circuit 134, which is coupled to an instruction translation lookaside buffer (TLB) 136, which is coupled to an instruction fetch circuit 138, which is coupled to a decode circuit 140. The decode circuit 140 (e.g., decode circuit) may decode instructions (e.g., macro-instructions), and generate as an output one or more micro-operations, micro-code entry points, micro-instructions, other instructions, or other control signals, which are decoded from, or which otherwise reflect, or are derived from, the original instructions. The decode circuit 140 may be implemented using various different mechanisms. Examples of suitable mechanisms include, but are not limited to, look-up tables, hardware implementations, programmable logic arrays (PLAs), microcode read only memories (ROMs), etc. In one embodiment, the core 100 includes a microcode ROM or other medium that stores microcode for certain macro-instructions (e.g., in decode circuit 140 or otherwise within the front end circuit 130). The decode circuit 140 is coupled to a rename/allocator circuit 152 in the execution engine circuit 150.

The execution engine circuit 150 includes the rename/allocator circuit 152 coupled to a retirement circuit 154 and a set of one or more scheduler circuit(s) 156. The scheduler circuit(s) 156 represents any number of different schedulers, including reservations stations, central instruction window, etc. The scheduler circuit(s) 156 is coupled to the physical register file(s) circuit(s) 158. Each of the physical register file(s) circuits 158 represents one or more physical register files, different ones of which store one or more different data types, such as scalar integer, scalar floating point, packed integer, packed floating point, vector integer, vector floating point, status (e.g., an instruction pointer that is the address of the next instruction to be executed), etc. In one embodiment, the physical register file(s) circuit 158 comprises a vector registers circuit, a write mask registers circuit, and a scalar registers circuit. These register circuits may provide architectural vector registers, vector mask registers, and general purpose registers. The physical register file(s) circuit(s) 158 is overlapped by the retirement circuit 154 to illustrate various ways in which register renaming and out-of-order execution may be implemented (e.g., using a reorder buffer(s) and a retirement register file(s); using a future file(s), a history buffer(s), and a retirement register file(s); using a register maps and a pool of registers; etc.). The retirement circuit 154 and the physical register file(s) circuit(s) 158 are coupled to the execution cluster(s) 160. The execution cluster(s) 160 includes a set of one or more execution circuits 162 (e.g., execution circuits) and a set of one or more memory access circuits 164. The execution circuits 162 may perform various operations (e.g., shifts, addition, subtraction, multiplication) and on various types of data (e.g., scalar floating point, packed integer, packed floating point, vector integer, vector floating point). While some embodiments may include a number of execution circuits dedicated to specific functions or sets of functions, other embodiments may include only one execution circuit or multiple execution circuits that all perform all functions. The scheduler circuit(s) 156, physical register file(s) circuit(s) 158, and execution cluster(s) 160 are shown as being possibly plural because certain embodiments create separate pipelines for certain types of data/operations (e.g., a scalar integer pipeline, a scalar floating point/packed integer/packed floating point/vector integer/vector floating point pipeline, and/or a memory access pipeline that each have their own scheduler circuit, physical register file(s) circuit, and/or execution cluster—and in the case of a separate memory access pipeline, certain embodiments are implemented in which only the execution cluster of this pipeline has the memory access circuit(s) 164). It should also be understood that where separate pipelines are used, one or more of these pipelines may be out-of-order issue/execution and the rest in-order.

The set of memory access circuits 164 is coupled to the memory circuit 170, which includes a load-type of data TLB circuit 172 and a store-type of data TLB circuit 173 coupled (e.g., via respective ports) to a data cache circuit 174 (e.g., level 1) coupled to a level 2 (L2) cache circuit 176. In one exemplary embodiment, the memory access circuits 164 may include a load circuit, a store address circuit, and a store data circuit, each of which is coupled to the load data TLB circuit 172 and/or store data TLB circuit 173 in the memory circuit 170. In certain embodiments, the instruction cache circuit 134 is further coupled to a level 2 (L2) cache circuit 176 in the memory circuit 170. In certain embodiments, the L2 cache circuit 176 is coupled to one or more other levels of cache and eventually to a main memory.

By way of example, the exemplary register renaming, out-of-order issue/execution core architecture may implement the pipeline 100 as follows: 1) the instruction fetch circuit 138 may perform a fetch and length decoding stages (e.g., stages 1002 and 1004 in FIG. 10A); 2) the decode circuit 140 may perform a decode stage (e.g., stage 1006 in FIG. 10A); 3) the rename/allocator circuit 152 may perform an allocation stage (e.g., stage 1008 in FIG. 10A) and renaming stage (e.g., stage 1010 in FIG. 10A); 4) the scheduler circuit(s) 156 may perform a schedule stage (e.g., stage 1012 in FIG. 10A); 5) the physical register file(s) circuit(s) 158 and the memory circuit 170 (e.g., orchestrator circuit 177) may perform a register read/memory read stage (e.g., stage 1014 in FIG. 10A); the execution cluster 160 may perform an execute stage (e.g., stage 1016 in FIG. 10A); 6) the memory circuit 170 (e.g., orchestrator circuit 177) and the physical register file(s) circuit(s) 158 may perform a write back/memory write stage (e.g., stage 1018 in FIG. 10A); 7) various circuits may be involved in an exception handling stage (e.g., stage 1022 in FIG. 10A); and 8) the retirement circuit 154 and the physical register file(s) circuit(s) 158 may perform a commit stage (e.g., stage 1024 in FIG. 10A).

The core 100 may support one or more instructions sets (e.g., the x86 instruction set (with some extensions that have been added with newer versions); the MIPS instruction set of MIPS Technologies of Sunnyvale, Calif.; the ARM instruction set (with optional additional extensions such as NEON) of ARM Holdings of Sunnyvale, Calif.), including the instruction(s) described herein. In one embodiment, the core 100 includes logic (e.g., logic circuitry) to support a packed data instruction set extension (e.g., AVX1, AVX2), thereby allowing the operations used by many multimedia applications to be performed using packed data.

It should be understood that the core may support multithreading (executing two or more parallel sets of operations or threads), and may do so in a variety of ways including time sliced multithreading, simultaneous multithreading (where a single physical core provides a logical core for each of the threads that physical core is simultaneously multithreading), or a combination thereof (e.g., time sliced fetching and decoding and simultaneous multithreading thereafter such as in the Intel® Hyper-Threading technology).

While register renaming is described in the context of out-of-order execution, it should be understood that register renaming may be used in an in-order architecture. While the illustrated embodiment of the processor also includes separate instruction and data cache circuits 134/174 and a shared L2 cache circuit 176, alternative embodiments may have a single internal cache for both instructions and data, such as, for example, a Level 1 (L1) internal cache, or multiple levels of internal cache. In some embodiments, the system may include a combination of an internal cache and an external cache that is external to the core and/or the processor. Alternatively, all of the cache may be external to the core and/or the processor.

FIG. 2 illustrates a load data translation lookaside buffer circuit 202 according to embodiments of the disclosure. Circuit 200 includes an input (e.g., queue) of one or more memory access requests 204 (e.g., load data requests). In one embodiment, memory access requests 204 is a load buffer (e.g., storage) in hardware. In certain embodiments, memory access request is from execution of an instruction, e.g., a request from an execution circuit(s) 162 in FIG. 1. In certain embodiments, memory access request is known to be a load data request (e.g., and not a store data request) as sent, and is thus sent to an input port of load data translation lookaside buffer (TLB) circuit 202 (e.g., and not sent to an input port of a store data TLB circuit, e.g., stored data TLB circuit 302 in FIG. 3). In one embodiment, load data TLB circuit 172 in FIG. 1 is an instance of load data TLB circuit 202.

In one embodiment, an execution circuit (e.g., execution unit), such as, but not limited to, execution circuit(s) 162 in FIG. 1, is to send load data requests to a port of load data TLB circuit 202 (e.g., port 171 in FIG. 1). In another embodiment, an execution circuit (e.g., execution unit), such as, but not limited to, execution circuit(s) 162 in FIG. 1, is to send (e.g., load data and store data) memory access requests to memory circuit (e.g., memory circuit 170 in FIG. 1), and the memory circuit is to determine if the memory access request is a load data request or a store data request, and then route a corresponding load data type of memory access request to a port of load data TLB circuit 202 (e.g., port(s) 171 in FIG. 1), e.g., and a corresponding store data type of memory access request to a port of a store data TLB circuit (e.g., store data TLB circuit 302 in FIG. 2) (e.g., port(s) 175 in FIG. 1).

A load data translation lookaside buffer circuit 202 may include one or more input ports, e.g., depicted as ports 1 through X, where X is any positive integer greater than one. In certain embodiments, each of a plurality of input ports of load data translation lookaside buffer circuit 202 is to service a respective load data request simultaneously, for example, each port receiving a different load data request that includes a virtual address to load data from, performing a look-up in load data translation table 208 for a corresponding physical address for that virtual address, and (e.g., assuming a hit for an entry in the table 208 having the mapping for that virtual address to its corresponding physical address) sending that load data request to that physical address in the data cache circuit 206 to be serviced. In one embodiment, data cache circuit 206 includes a plurality of input ports therein (e.g., a port into a respective bank of a plurality of banks of the cache).

A load data translation lookaside buffer circuit 202 may include one or more output ports, e.g., depicted as ports 1 through X, where X is any positive integer greater than one. The X number of output ports may be the same as the X number of input ports or a different number. In certain embodiments, each of a plurality of output ports of load data translation lookaside buffer circuit 202 is to service a respective load data request simultaneously, e.g., by sending the physical address for the load data request into data cache circuit 206 for servicing, e.g., such that the data being loaded is sent to its requested location (e.g., a register file of a core). In certain embodiments, each of a plurality of input ports and/or output ports of load data translation lookaside buffer circuit 202 is to service a respective load data request simultaneously, e.g., such that X number (e.g., where X is the number of input ports of load data translation lookaside buffer circuit 202) of input load data requests are executed in a single cycle (e.g., of the processor core) and/or X number (e.g., where X is the number of output ports of load data translation lookaside buffer circuit 202) of input load data requests are executed in a single cycle.

In certain embodiments, load data translation lookaside buffer circuit 202 includes a load data translation policy(s) 210 storage to set the policy(s), for example, one or more policy settings that indicate an update (e.g., fill) policy, size (e.g., number of entries), associativity, which operations are looked up in that circuit 202 (e.g., only load data requests), or any combination thereof.

In certain embodiments, load data translation lookaside buffer circuit 202 includes load data translation table 208 to store virtual address to physical address mappings, e.g., to convert a virtual address (e.g., as seen by a program running on the processor) to a physical address (e.g., the address in memory hardware). Load data translation table 206 is to be updated with (e.g., recently used) virtual-to-physical memory address translations, e.g., such that the translation does not have to be performed on each virtual address present to obtain the physical memory address corresponding to that virtual address. If the virtual address entry is not in the TLB, a processor (e.g., memory circuit, such as, but not limited to, a memory management circuit) may perform a (e.g., multiple cycle) page walk to determine the virtual-to-physical memory address translation.

In FIG. 2, first entry 208-1 in load data translation table 208 is to store a mapping for a first virtual address to a first physical address, and up to M (e.g., where M is any integer greater than one) entries, e.g., such that entry 208-M may store a mapping for a second, different virtual address to a second, different physical address. Optionally, load data translation table 208 may include a field in each entry for other data, that data including, but not limited to, an indication of the execution resources that are allowed to use that translation, or other attributes (e.g., one or more of a read/write permission and/or a user/supervisor level). In one embodiment, a load TLB is shared by a plurality of cores or other execution resources. Examples of execution resources include a thread, a process, a context, a virtual machine, a logical processor, a hardware thread, a core, and a processor. In one embodiment, a TLB is shared by a plurality of threads and the other field of load data translation table 208 is utilized (e.g., by setting a respective bit) to indicate that a virtual address to physical address translation for that entry is valid for a particular thread or threads. In one embodiment, clearing of the sharing bits (e.g., bit positions) does not clear or affect any other field in an entry of load data translation table 208, e.g., the stale data remains. In one embodiment, clearing of all (e.g., the remaining) set sharing bits (e.g., bit positions) causes a clear of one or more (e.g., all) of the other fields in that entry of load data translation table 208.

In certain embodiments, memory circuit (e.g., memory circuit 170 in FIG. 1) is to set each bit position in an entry of load data translation table 208 when the corresponding thread is to use the virtual to physical address translation (e.g., mapping) for that entry.

FIG. 3 illustrates a store data translation lookaside buffer circuit according to embodiments of the disclosure. Circuit 300 includes an input (e.g., queue) of one or more memory access requests 304 (e.g., store data requests). In one embodiment, memory access requests 304 is a store buffer (e.g., storage) in hardware. In certain embodiments, memory access request is from execution of an instruction, e.g., a request from an execution circuit(s) 162 in FIG. 1. In certain embodiments, memory access request is known to be a store data request (e.g., and not a load data request) as sent, and is thus sent to an input port of store data translation lookaside buffer (TLB) circuit 302 (e.g., and not sent to an input port of a store data TLB circuit, e.g., stored data TLB circuit 302 in FIG. 3). In one embodiment, store data TLB circuit 173 in FIG. 1 is an instance of store data TLB circuit 302.

In one embodiment, an execution circuit (e.g., execution unit), such as, but not limited to, execution circuit(s) 162 in FIG. 1, is to send store data requests to a port of store data TLB circuit 302 (e.g., port 175 in FIG. 1). In another embodiment, an execution circuit (e.g., execution unit), such as, but not limited to, execution circuit(s) 162 in FIG. 1, is to send (e.g., load data and store data) memory access requests to memory circuit (e.g., memory circuit 170 in FIG. 1), and the memory circuit is to determine if the memory access request is a load data request or a store data request, and then route a corresponding store data type of memory access request to a port of store data TLB circuit 302 (e.g., port(s) 175 in FIG. 1), e.g., and a corresponding load data type of memory access request to a port of a load data TLB circuit (e.g., load data TLB circuit 202 in FIG. 2) (e.g., port(s) 171 in FIG. 1).

A store data translation lookaside buffer circuit 302 may include one or more input ports, e.g., depicted as ports 1 through Y, where Y is any positive integer greater than one. In certain embodiments, each of a plurality of input ports of store data translation lookaside buffer circuit 302 is to service a respective store data request simultaneously, for example, each port receiving a different store data request that includes a virtual address to store data from, performing a look-up in store data translation table 308 for a corresponding physical address for that virtual address, and (e.g., assuming a hit for an entry in the table 308 having the mapping for that virtual address to its corresponding physical address) sending that store data request (e.g., including the data that is to be stored (e.g., payload)) to that physical address in the data cache circuit 306 to be serviced. In one embodiment, data cache circuit 306 includes a plurality of input ports therein (e.g., a port into a respective bank of a plurality of banks of the cache).

A store data translation lookaside buffer circuit 302 may include one or more output ports, e.g., depicted as ports 1 through Y, where Y is any positive integer greater than one. The Y number of output ports may be the same as the Y number of input ports or a different number. In certain embodiments, each of a plurality of output ports of store data translation lookaside buffer circuit 302 is to service a respective store data request simultaneously, e.g., by sending the physical address for the store data request into data cache circuit 306 (e.g., including the data that is to be stored (e.g., payload)) for servicing, e.g., such that the data being stored is sent to its requested location (e.g., as sourced from a register file of a core). In certain embodiments, each of a plurality of input ports and/or output ports of store data translation lookaside buffer circuit 302 is to service a respective store data request simultaneously, e.g., such that Y number (e.g., where Y is the number of input ports of store data translation lookaside buffer circuit 302) of input store data requests are executed in a single cycle (e.g., of the processor core) and/or Y number (e.g., where Y is the number of output ports of store data translation lookaside buffer circuit 302) of input store data requests are executed in a single cycle.

In certain embodiments, store data translation lookaside buffer circuit 302 includes a store data translation policy(s) 310 storage to set the policy(s), for example, one or more policy settings that indicate an update (e.g., fill) policy, size (e.g., number of entries), associativity, which operations are looked up in that circuit 302 (e.g., only store data requests), or any combination thereof.

In certain embodiments, store data translation lookaside buffer circuit 302 includes store data translation table 308 to store virtual address to physical address mappings, e.g., to convert a virtual address (e.g., as seen by a program running on the processor) to a physical address (e.g., the address in memory hardware). Store data translation table 306 is to be updated with (e.g., recently used) virtual-to-physical memory address translations, e.g., such that the translation does not have to be performed on each virtual address present to obtain the physical memory address corresponding to that virtual address. If the virtual address entry is not in the TLB, a processor (e.g., memory circuit, such as, but not limited to, a memory management circuit) may perform a (e.g., multiple cycle) page walk to determine the virtual-to-physical memory address translation.

In FIG. 3, first entry 308-1 in store data translation table 308 is to store a mapping for a first virtual address to a first physical address, and up to N (e.g., where N is any integer greater than one) entries, e.g., such that entry 308-N may store a mapping for a second, different virtual address to a second, different physical address. Optionally, store data translation table 308 may include a field in each entry for other data, that data including, but not limited to, an indication of the execution resources that are allowed to use that translation, or other attributes (e.g., one or more of a read/write permission and/or a user/supervisor level). In one embodiment, a store TLB is shared by a plurality of cores or other execution resources. Examples of execution resources include a thread, a process, a context, a virtual machine, a logical processor, a hardware thread, a core, and a processor. In one embodiment, a TLB is shared by a plurality of threads and the other field of store data translation table 308 is utilized (e.g., by setting a respective bit) to indicate that a virtual address to physical address translation for that entry is valid for a particular thread or threads. In one embodiment, clearing of the sharing bits (e.g., bit positions) does not clear or affect any other field in an entry of store data translation table 308, e.g., the stale data remains. In one embodiment, clearing of all (e.g., the remaining) set sharing bits (e.g., bit positions) causes a clear of one or more (e.g., all) of the other fields in that entry of store data translation table 308.

In certain embodiments, memory circuit (e.g., memory circuit 170 in FIG. 1) is to set each bit position in an entry of store data translation table 308 when the corresponding thread is to use the virtual to physical address translation (e.g., mapping) for that entry.

FIG. 4 illustrates a flow diagram 400 for a load data request according to embodiments of the disclosure. Depicted flow 400 includes receiving a memory access request of an instruction from a processor with a memory circuit 402, determining, by the memory circuit, that the memory access request is a load data request 404, sending the memory access request to a load data translation lookaside buffer circuit when the memory access request is the load data request to determine a physical address for a virtual address of the memory access request 406, and performing a load for the memory access request at the physical address 408.

FIG. 5 illustrates a flow diagram 500 for a store data request according to embodiments of the disclosure. Depicted flow 500 includes receiving a memory access request of an instruction from a processor with a memory circuit 502, determining, by the memory circuit, that the memory access request is a store data request 504, sending the memory access request to a store data translation lookaside buffer circuit when the memory access request is the store data request to determine a physical address for a virtual address of the memory access request 506, and performing a store for the memory access request at the physical address 508.

FIG. 6 illustrates a flow diagram 600 according to embodiments of the disclosure. Depicted flow 600 includes receiving a memory access request of an instruction from a processor with a memory circuit 602, determining, by the memory circuit, when the memory access request is a load data request or a store data request 604, sending the memory access request to a load data translation lookaside buffer circuit when the memory access request is the load data request and to a store data translation lookaside buffer circuit separate and distinct from the load data translation lookaside buffer circuit when the memory access request is the store data request to determine a physical address for a virtual address of the memory access request 606, and performing a memory access for the memory access request at the physical address 608.

Exemplary architectures, systems, etc. that the above may be used in are detailed below.

At least some embodiments of the disclosed technologies can be described in view of the following examples:

-   Example 1. A processor comprising:     -   a decode circuit to decode instructions into decoded         instructions;     -   an execution circuit to execute the decoded instructions; and     -   a memory circuit comprising a load data translation lookaside         buffer circuit and a store data translation lookaside buffer         circuit separate and distinct from the load data translation         lookaside buffer circuit, wherein the memory circuit sends a         memory access request of the instructions to the load data         translation lookaside buffer circuit when the memory access         request is a load data request and to the store data translation         lookaside buffer circuit when the memory access request is a         store data request to determine a physical address for a virtual         address of the memory access request, and the load data         translation lookaside buffer circuit and the store data         translation lookaside buffer circuit are different sizes and         different associativity. -   Example 2. The processor of example 1, wherein the load data     translation lookaside buffer circuit comprises more entry storage     locations than the store data translation lookaside buffer circuit. -   Example 3. The processor of example 1, wherein the load data     translation lookaside buffer circuit is updated on each load     operation and each store operation of the instructions. -   Example 4. The processor of example 3, wherein the store data     translation lookaside buffer circuit is updated only by each store     operation of the instructions. -   Example 5. The processor of example 1, wherein the store data     translation lookaside buffer circuit is updated independently of the     load data translation lookaside buffer circuit. -   Example 6. The processor of example 1, wherein the store data     translation lookaside buffer circuit is updated only by each store     operation of the instructions. -   Example 7. The processor of example 1, wherein the load data request     is to be input into one of a plurality of load ports of the load     data translation lookaside buffer circuit. -   Example 8. The processor of example 1, wherein the store data     request is to be input into one of a plurality of store ports of the     store data translation lookaside buffer circuit. -   Example 9. A method comprising:     -   receiving a memory access request of an instruction from a         processor with a memory circuit;     -   determining, by the memory circuit, when the memory access         request is a load data request or a store data request;     -   sending the memory access request to a load data translation         lookaside buffer circuit when the memory access request is the         load data request and to a store data translation lookaside         buffer circuit separate and distinct from the load data         translation lookaside buffer circuit when the memory access         request is the store data request to determine a physical         address for a virtual address of the memory access request,         wherein the load data translation lookaside buffer circuit and         the store data translation lookaside buffer circuit are         different sizes and different associativity; and     -   performing a memory access for the memory access request at the         physical address. -   Example 10. The method of example 9, wherein the load data     translation lookaside buffer circuit comprises more entry storage     locations than the store data translation lookaside buffer circuit. -   Example 11. The method of example 9, further comprising updating the     load data translation lookaside buffer circuit on each load     operation and each store operation of the instructions. -   Example 12. The method of example 11, further comprising updating     the store data translation lookaside buffer circuit only by each     store operation of the instructions. -   Example 13. The method of example 9, further comprising updating the     store data translation lookaside buffer circuit independently of     updating the load data translation lookaside buffer circuit. -   Example 14. The method of example 9, further comprising updating the     store data translation lookaside buffer circuit only by each store     operation of the instructions. -   Example 15. The method of example 9, wherein the sending the memory     access request comprises inputting the load data request into one of     a plurality of load ports of the load data translation lookaside     buffer circuit. -   Example 16. The method of example 9, wherein the sending the memory     access request comprises inputting the store data request into one     of a plurality of store ports of the store data translation     lookaside buffer circuit. -   Example 17. A non-transitory machine readable medium that stores     code that when executed by a machine causes the machine to perform a     method comprising:     -   receiving a memory access request of an instruction from a         processor with a memory circuit;     -   determining, by the memory circuit, when the memory access         request is a load data request or a store data request;     -   sending the memory access request to a load data translation         lookaside buffer circuit when the memory access request is the         load data request and to a store data translation lookaside         buffer circuit separate and distinct from the load data         translation lookaside buffer circuit when the memory access         request is the store data request to determine a physical         address for a virtual address of the memory access request,         wherein the load data translation lookaside buffer circuit and         the store data translation lookaside buffer circuit are         different sizes and different associativity; and     -   performing a memory access for the memory access request at the         physical address. -   Example 18. The non-transitory machine readable medium of example     17, wherein the load data translation lookaside buffer circuit     comprises more entry storage locations than the store data     translation lookaside buffer circuit. -   Example 19. The non-transitory machine readable medium of example     17, further comprising updating the load data translation lookaside     buffer circuit on each load operation and each store operation of     the instructions. -   Example 20. The non-transitory machine readable medium of example     19, further comprising updating the store data translation lookaside     buffer circuit only by each store operation of the instructions. -   Example 21. The non-transitory machine readable medium of example     17, further comprising updating the store data translation lookaside     buffer circuit independently of updating the load data translation     lookaside buffer circuit. -   Example 22. The non-transitory machine readable medium of example     17, further comprising updating the store data translation lookaside     buffer circuit only by each store operation of the instructions. -   Example 23. The non-transitory machine readable medium of example     17, wherein the sending the memory access request comprises     inputting the load data request into one of a plurality of load     ports of the load data translation lookaside buffer circuit. -   Example 24. The non-transitory machine readable medium of example     17, wherein the sending the memory access request comprises     inputting the store data request into one of a plurality of store     ports of the store data translation lookaside buffer circuit. -   Example 25. A system comprising:     -   a processor core comprising:         -   a decode circuit to decode instructions into decoded             instructions, and         -   an execution circuit to execute the decoded instructions;             and     -   a memory circuit coupled to the processor core and comprising a         load data translation lookaside buffer circuit and a store data         translation lookaside buffer circuit separate and distinct from         the load data translation lookaside buffer circuit, wherein the         memory circuit sends a memory access request of the instructions         to the load data translation lookaside buffer circuit when the         memory access request is a load data request and to the store         data translation lookaside buffer circuit when the memory access         request is a store data request to determine a physical address         for a virtual address of the memory access request, and the load         data translation lookaside buffer circuit and the store data         translation lookaside buffer circuit are different sizes and         different associativity. -   Example 26. The system of example 25, wherein the load data     translation lookaside buffer circuit comprises more entry storage     locations than the store data translation lookaside buffer circuit. -   Example 27. The system of example 25, wherein the load data     translation lookaside buffer circuit is updated on each load     operation and each store operation of the instructions. -   Example 28. The system of example 27, wherein the store data     translation lookaside buffer circuit is updated only by each store     operation of the instructions. -   Example 29. The system of example 25, wherein the store data     translation lookaside buffer circuit is updated independently of the     load data translation lookaside buffer circuit. -   Example 30. The system of example 25, wherein the store data     translation lookaside buffer circuit is updated only by each store     operation of the instructions. -   Example 31. The system of example 25, wherein the load data request     is to be input into one of a plurality of load ports of the load     data translation lookaside buffer circuit. -   Example 32. The system of example 25, wherein the store data request     is to be input into one of a plurality of store ports of the store     data translation lookaside buffer circuit.

In yet another embodiment, an apparatus comprises a data storage device that stores code that when executed by a hardware processor causes the hardware processor to perform any method disclosed herein. An apparatus may be as described in the detailed description. A method may be as described in the detailed description.

An instruction set may include one or more instruction formats. A given instruction format may define various fields (e.g., number of bits, location of bits) to specify, among other things, the operation to be performed (e.g., opcode) and the operand(s) on which that operation is to be performed and/or other data field(s) (e.g., mask). Some instruction formats are further broken down though the definition of instruction templates (or subformats). For example, the instruction templates of a given instruction format may be defined to have different subsets of the instruction format's fields (the included fields are typically in the same order, but at least some have different bit positions because there are less fields included) and/or defined to have a given field interpreted differently. Thus, each instruction of an ISA is expressed using a given instruction format (and, if defined, in a given one of the instruction templates of that instruction format) and includes fields for specifying the operation and the operands. For example, an exemplary ADD instruction has a specific opcode and an instruction format that includes an opcode field to specify that opcode and operand fields to select operands (source1/destination and source2); and an occurrence of this ADD instruction in an instruction stream will have specific contents in the operand fields that select specific operands. A set of SIMD extensions referred to as the Advanced Vector Extensions (AVX) (AVX1 and AVX2) and using the Vector Extensions (VEX) coding scheme has been released and/or published (e.g., see Intel® 64 and IA-32 Architectures Software Developer's Manual, November 2018; and see Intel® Architecture Instruction Set Extensions Programming Reference, October 2018).

Exemplary Instruction Formats

Embodiments of the instruction(s) described herein may be embodied in different formats. Additionally, exemplary systems, architectures, and pipelines are detailed below. Embodiments of the instruction(s) may be executed on such systems, architectures, and pipelines, but are not limited to those detailed.

Generic Vector Friendly Instruction Format

A vector friendly instruction format is an instruction format that is suited for vector instructions (e.g., there are certain fields specific to vector operations). While embodiments are described in which both vector and scalar operations are supported through the vector friendly instruction format, alternative embodiments use only vector operations the vector friendly instruction format.

FIGS. 7A-7B are block diagrams illustrating a generic vector friendly instruction format and instruction templates thereof according to embodiments of the disclosure. FIG. 7A is a block diagram illustrating a generic vector friendly instruction format and class A instruction templates thereof according to embodiments of the disclosure; while FIG. 7B is a block diagram illustrating the generic vector friendly instruction format and class B instruction templates thereof according to embodiments of the disclosure. Specifically, a generic vector friendly instruction format 700 for which are defined class A and class B instruction templates, both of which include no memory access 705 instruction templates and memory access 720 instruction templates. The term generic in the context of the vector friendly instruction format refers to the instruction format not being tied to any specific instruction set.

While embodiments of the disclosure will be described in which the vector friendly instruction format supports the following: a 64 byte vector operand length (or size) with 32 bit (4 byte) or 64 bit (8 byte) data element widths (or sizes) (and thus, a 64 byte vector consists of either 16 doubleword-size elements or alternatively, 8 quadword-size elements); a 64 byte vector operand length (or size) with 16 bit (2 byte) or 8 bit (1 byte) data element widths (or sizes); a 32 byte vector operand length (or size) with 32 bit (4 byte), 64 bit (8 byte), 16 bit (2 byte), or 8 bit (1 byte) data element widths (or sizes); and a 16 byte vector operand length (or size) with 32 bit (4 byte), 64 bit (8 byte), 16 bit (2 byte), or 8 bit (1 byte) data element widths (or sizes); alternative embodiments may support more, less and/or different vector operand sizes (e.g., 256 byte vector operands) with more, less, or different data element widths (e.g., 128 bit (16 byte) data element widths).

The class A instruction templates in FIG. 7A include: 1) within the no memory access 705 instruction templates there is shown a no memory access, full round control type operation 710 instruction template and a no memory access, data transform type operation 715 instruction template; and 2) within the memory access 720 instruction templates there is shown a memory access, temporal 725 instruction template and a memory access, non-temporal 730 instruction template. The class B instruction templates in FIG. 7B include: 1) within the no memory access 705 instruction templates there is shown a no memory access, write mask control, partial round control type operation 712 instruction template and a no memory access, write mask control, vsize type operation 717 instruction template; and 2) within the memory access 720 instruction templates there is shown a memory access, write mask control 727 instruction template.

The generic vector friendly instruction format 700 includes the following fields listed below in the order illustrated in FIGS. 7A-7B.

Format field 740—a specific value (an instruction format identifier value) in this field uniquely identifies the vector friendly instruction format, and thus occurrences of instructions in the vector friendly instruction format in instruction streams. As such, this field is optional in the sense that it is not needed for an instruction set that has only the generic vector friendly instruction format.

Base operation field 742—its content distinguishes different base operations.

Register index field 744—its content, directly or through address generation, specifies the locations of the source and destination operands, be they in registers or in memory. These include a sufficient number of bits to select N registers from a PxQ (e.g. 32×512, 16×128, 32×1024, 64×1024) register file. While in one embodiment N may be up to three sources and one destination register, alternative embodiments may support more or less sources and destination registers (e.g., may support up to two sources where one of these sources also acts as the destination, may support up to three sources where one of these sources also acts as the destination, may support up to two sources and one destination).

Modifier field 746—its content distinguishes occurrences of instructions in the generic vector instruction format that specify memory access from those that do not; that is, between no memory access 705 instruction templates and memory access 720 instruction templates. Memory access operations read and/or write to the memory hierarchy (in some cases specifying the source and/or destination addresses using values in registers), while non-memory access operations do not (e.g., the source and destinations are registers). While in one embodiment this field also selects between three different ways to perform memory address calculations, alternative embodiments may support more, less, or different ways to perform memory address calculations.

Augmentation operation field 750—its content distinguishes which one of a variety of different operations to be performed in addition to the base operation. This field is context specific. In one embodiment of the disclosure, this field is divided into a class field 768, an alpha field 752, and a beta field 754. The augmentation operation field 750 allows common groups of operations to be performed in a single instruction rather than 2, 3, or 4 instructions.

Scale field 760—its content allows for the scaling of the index field's content for memory address generation (e.g., for address generation that uses 2^(scale)*index+base).

Displacement Field 762A—its content is used as part of memory address generation (e.g., for address generation that uses 2^(scale)*index+base+displacement).

Displacement Factor Field 762B (note that the juxtaposition of displacement field 762A directly over displacement factor field 762B indicates one or the other is used)—its content is used as part of address generation; it specifies a displacement factor that is to be scaled by the size of a memory access (N)—where N is the number of bytes in the memory access (e.g., for address generation that uses 2^(scale)*index+base+scaled displacement). Redundant low-order bits are ignored and hence, the displacement factor field's content is multiplied by the memory operands total size (N) in order to generate the final displacement to be used in calculating an effective address. The value of N is determined by the processor hardware at runtime based on the full opcode field 774 (described later herein) and the data manipulation field 754C. The displacement field 762A and the displacement factor field 762B are optional in the sense that they are not used for the no memory access 705 instruction templates and/or different embodiments may implement only one or none of the two.

Data element width field 764—its content distinguishes which one of a number of data element widths is to be used (in some embodiments for all instructions; in other embodiments for only some of the instructions). This field is optional in the sense that it is not needed if only one data element width is supported and/or data element widths are supported using some aspect of the opcodes.

Write mask field 770—its content controls, on a per data element position basis, whether that data element position in the destination vector operand reflects the result of the base operation and augmentation operation. Class A instruction templates support merging-writemasking, while class B instruction templates support both merging- and zeroing-writemasking. When merging, vector masks allow any set of elements in the destination to be protected from updates during the execution of any operation (specified by the base operation and the augmentation operation); in other one embodiment, preserving the old value of each element of the destination where the corresponding mask bit has a 0. In contrast, when zeroing vector masks allow any set of elements in the destination to be zeroed during the execution of any operation (specified by the base operation and the augmentation operation); in one embodiment, an element of the destination is set to 0 when the corresponding mask bit has a 0 value. A subset of this functionality is the ability to control the vector length of the operation being performed (that is, the span of elements being modified, from the first to the last one); however, it is not necessary that the elements that are modified be consecutive. Thus, the write mask field 770 allows for partial vector operations, including loads, stores, arithmetic, logical, etc. While embodiments of the disclosure are described in which the write mask field's 770 content selects one of a number of write mask registers that contains the write mask to be used (and thus the write mask field's 770 content indirectly identifies that masking to be performed), alternative embodiments instead or additional allow the mask write field's 770 content to directly specify the masking to be performed.

Immediate field 772—its content allows for the specification of an immediate. This field is optional in the sense that is it not present in an implementation of the generic vector friendly format that does not support immediate and it is not present in instructions that do not use an immediate.

Class field 768—its content distinguishes between different classes of instructions. With reference to FIGS. 7A-B, the contents of this field select between class A and class B instructions. In FIGS. 7A-B, rounded corner squares are used to indicate a specific value is present in a field (e.g., class A 768A and class B 768B for the class field 768 respectively in FIGS. 7A-B).

Instruction Templates of Class A

In the case of the non-memory access 705 instruction templates of class A, the alpha field 752 is interpreted as an RS field 752A, whose content distinguishes which one of the different augmentation operation types are to be performed (e.g., round 752A.1 and data transform 752A.2 are respectively specified for the no memory access, round type operation 710 and the no memory access, data transform type operation 715 instruction templates), while the beta field 754 distinguishes which of the operations of the specified type is to be performed. In the no memory access 705 instruction templates, the scale field 760, the displacement field 762A, and the displacement scale filed 762B are not present.

No-Memory Access Instruction Templates—Full Round Control Type Operation

In the no memory access full round control type operation 710 instruction template, the beta field 754 is interpreted as a round control field 754A, whose content(s) provide static rounding. While in the described embodiments of the disclosure the round control field 754A includes a suppress all floating point exceptions (SAE) field 756 and a round operation control field 758, alternative embodiments may support may encode both these concepts into the same field or only have one or the other of these concepts/fields (e.g., may have only the round operation control field 758).

SAE field 756—its content distinguishes whether or not to disable the exception event reporting; when the SAE field's 756 content indicates suppression is enabled, a given instruction does not report any kind of floating-point exception flag and does not raise any floating point exception handler.

Round operation control field 758—its content distinguishes which one of a group of rounding operations to perform (e.g., Round-up, Round-down, Round-towards-zero and Round-to-nearest). Thus, the round operation control field 758 allows for the changing of the rounding mode on a per instruction basis. In one embodiment of the disclosure where a processor includes a control register for specifying rounding modes, the round operation control field's 750 content overrides that register value.

No Memory Access Instruction Templates—Data Transform Type Operation

In the no memory access data transform type operation 715 instruction template, the beta field 754 is interpreted as a data transform field 754B, whose content distinguishes which one of a number of data transforms is to be performed (e.g., no data transform, swizzle, broadcast).

In the case of a memory access 720 instruction template of class A, the alpha field 752 is interpreted as an eviction hint field 752B, whose content distinguishes which one of the eviction hints is to be used (in FIG. 7A, temporal 752B.1 and non-temporal 752B.2 are respectively specified for the memory access, temporal 725 instruction template and the memory access, non-temporal 730 instruction template), while the beta field 754 is interpreted as a data manipulation field 754C, whose content distinguishes which one of a number of data manipulation operations (also known as primitives) is to be performed (e.g., no manipulation; broadcast; up conversion of a source; and down conversion of a destination). The memory access 720 instruction templates include the scale field 760, and optionally the displacement field 762A or the displacement scale field 762B.

Vector memory instructions perform vector loads from and vector stores to memory, with conversion support. As with regular vector instructions, vector memory instructions transfer data from/to memory in a data element-wise fashion, with the elements that are actually transferred is dictated by the contents of the vector mask that is selected as the write mask.

Memory Access Instruction Templates—Temporal

Temporal data is data likely to be reused soon enough to benefit from caching. This is, however, a hint, and different processors may implement it in different ways, including ignoring the hint entirely.

Memory Access Instruction Templates—Non-Temporal

Non-temporal data is data unlikely to be reused soon enough to benefit from caching in the 1st-level cache and should be given priority for eviction. This is, however, a hint, and different processors may implement it in different ways, including ignoring the hint entirely.

Instruction Templates of Class B

In the case of the instruction templates of class B, the alpha field 752 is interpreted as a write mask control (Z) field 752C, whose content distinguishes whether the write masking controlled by the write mask field 770 should be a merging or a zeroing.

In the case of the non-memory access 705 instruction templates of class B, part of the beta field 754 is interpreted as an RL field 757A, whose content distinguishes which one of the different augmentation operation types are to be performed (e.g., round 757A.1 and vector length (VSIZE) 757A.2 are respectively specified for the no memory access, write mask control, partial round control type operation 712 instruction template and the no memory access, write mask control, VSIZE type operation 717 instruction template), while the rest of the beta field 754 distinguishes which of the operations of the specified type is to be performed. In the no memory access 705 instruction templates, the scale field 760, the displacement field 762A, and the displacement scale filed 762B are not present.

In the no memory access, write mask control, partial round control type operation 710 instruction template, the rest of the beta field 754 is interpreted as a round operation field 759A and exception event reporting is disabled (a given instruction does not report any kind of floating-point exception flag and does not raise any floating point exception handler).

Round operation control field 759A—just as round operation control field 758, its content distinguishes which one of a group of rounding operations to perform (e.g., Round-up, Round-down, Round-towards-zero and Round-to-nearest). Thus, the round operation control field 759A allows for the changing of the rounding mode on a per instruction basis. In one embodiment of the disclosure where a processor includes a control register for specifying rounding modes, the round operation control field's 750 content overrides that register value.

In the no memory access, write mask control, VSIZE type operation 717 instruction template, the rest of the beta field 754 is interpreted as a vector length field 759B, whose content distinguishes which one of a number of data vector lengths is to be performed on (e.g., 128, 256, or 512 byte).

In the case of a memory access 720 instruction template of class B, part of the beta field 754 is interpreted as a broadcast field 757B, whose content distinguishes whether or not the broadcast type data manipulation operation is to be performed, while the rest of the beta field 754 is interpreted the vector length field 759B. The memory access 720 instruction templates include the scale field 760, and optionally the displacement field 762A or the displacement scale field 762B.

With regard to the generic vector friendly instruction format 700, a full opcode field 774 is shown including the format field 740, the base operation field 742, and the data element width field 764. While one embodiment is shown where the full opcode field 774 includes all of these fields, the full opcode field 774 includes less than all of these fields in embodiments that do not support all of them. The full opcode field 774 provides the operation code (opcode).

The augmentation operation field 750, the data element width field 764, and the write mask field 770 allow these features to be specified on a per instruction basis in the generic vector friendly instruction format.

The combination of write mask field and data element width field create typed instructions in that they allow the mask to be applied based on different data element widths.

The various instruction templates found within class A and class B are beneficial in different situations. In some embodiments of the disclosure, different processors or different cores within a processor may support only class A, only class B, or both classes. For instance, a high performance general purpose out-of-order core intended for general-purpose computing may support only class B, a core intended primarily for graphics and/or scientific (throughput) computing may support only class A, and a core intended for both may support both (of course, a core that has some mix of templates and instructions from both classes but not all templates and instructions from both classes is within the purview of the disclosure). Also, a single processor may include multiple cores, all of which support the same class or in which different cores support different class. For instance, in a processor with separate graphics and general purpose cores, one of the graphics cores intended primarily for graphics and/or scientific computing may support only class A, while one or more of the general purpose cores may be high performance general purpose cores with out of order execution and register renaming intended for general-purpose computing that support only class B. Another processor that does not have a separate graphics core, may include one more general purpose in-order or out-of-order cores that support both class A and class B. Of course, features from one class may also be implement in the other class in different embodiments of the disclosure. Programs written in a high level language would be put (e.g., just in time compiled or statically compiled) into an variety of different executable forms, including: 1) a form having only instructions of the class(es) supported by the target processor for execution; or 2) a form having alternative routines written using different combinations of the instructions of all classes and having control flow code that selects the routines to execute based on the instructions supported by the processor which is currently executing the code.

Exemplary Specific Vector Friendly Instruction Format

FIG. 8 is a block diagram illustrating an exemplary specific vector friendly instruction format according to embodiments of the disclosure. FIG. 8 shows a specific vector friendly instruction format 800 that is specific in the sense that it specifies the location, size, interpretation, and order of the fields, as well as values for some of those fields. The specific vector friendly instruction format 800 may be used to extend the x86 instruction set, and thus some of the fields are similar or the same as those used in the existing x86 instruction set and extension thereof (e.g., AVX). This format remains consistent with the prefix encoding field, real opcode byte field, MOD R/M field, SIB field, displacement field, and immediate fields of the existing x86 instruction set with extensions. The fields from FIG. 7 into which the fields from FIG. 8 map are illustrated.

It should be understood that, although embodiments of the disclosure are described with reference to the specific vector friendly instruction format 800 in the context of the generic vector friendly instruction format 700 for illustrative purposes, the disclosure is not limited to the specific vector friendly instruction format 800 except where claimed. For example, the generic vector friendly instruction format 700 contemplates a variety of possible sizes for the various fields, while the specific vector friendly instruction format 800 is shown as having fields of specific sizes. By way of specific example, while the data element width field 764 is illustrated as a one bit field in the specific vector friendly instruction format 800, the disclosure is not so limited (that is, the generic vector friendly instruction format 700 contemplates other sizes of the data element width field 764).

The generic vector friendly instruction format 700 includes the following fields listed below in the order illustrated in FIG. 8A.

EVEX Prefix (Bytes 0-3) 802—is encoded in a four-byte form.

Format Field 740 (EVEX Byte 0, bits [7:0])—the first byte (EVEX Byte 0) is the format field 740 and it contains 0×62 (the unique value used for distinguishing the vector friendly instruction format in one embodiment of the disclosure).

The second-fourth bytes (EVEX Bytes 1-3) include a number of bit fields providing specific capability.

REX field 805 (EVEX Byte 1, bits [7-5])—consists of a EVEX.R bit field (EVEX Byte 1, bit [7]—R), EVEX.X bit field (EVEX byte 1, bit [6]—X), and 757BEX byte 1, bit[5]—B). The EVEX.R, EVEX.X, and EVEX.B bit fields provide the same functionality as the corresponding VEX bit fields, and are encoded using 1s complement form, i.e. ZMM0 is encoded as 1111B, ZMM15 is encoded as 0000B. Other fields of the instructions encode the lower three bits of the register indexes as is known in the art (rrr, xxx, and bbb), so that Rrrr, Xxxx, and Bbbb may be formed by adding EVEX.R, EVEX.X, and EVEX.B.

REX′ field 710—this is the first part of the REX′ field 710 and is the EVEX.R′ bit field (EVEX Byte 1, bit [4]—R′) that is used to encode either the upper 16 or lower 16 of the extended 32 register set. In one embodiment of the disclosure, this bit, along with others as indicated below, is stored in bit inverted format to distinguish (in the well-known x86 32-bit mode) from the BOUND instruction, whose real opcode byte is 62, but does not accept in the MOD RIM field (described below) the value of 11 in the MOD field; alternative embodiments of the disclosure do not store this and the other indicated bits below in the inverted format. A value of 1 is used to encode the lower 16 registers. In other words, R′Rrrr is formed by combining EVEX.R′, EVEX.R, and the other RRR from other fields.

Opcode map field 815 (EVEX byte 1, bits [3:0]—mmmm)—its content encodes an implied leading opcode byte (0F, 0F 38, or 0F 3).

Data element width field 764 (EVEX byte 2, bit [7]—W)—is represented by the notation EVEX.W. EVEX.W is used to define the granularity (size) of the datatype (either 32-bit data elements or 64-bit data elements).

EVEX.vvvv 820 (EVEX Byte 2, bits [6:3]-vvvv)—the role of EVEX.vvvv may include the following: 1) EVEX.vvvv encodes the first source register operand, specified in inverted (1s complement) form and is valid for instructions with 2 or more source operands; 2) EVEX.vvvv encodes the destination register operand, specified in 1s complement form for certain vector shifts; or 3) EVEX.vvvv does not encode any operand, the field is reserved and should contain 1111b. Thus, EVEX.vvvv field 820 encodes the 4 low-order bits of the first source register specifier stored in inverted (1s complement) form. Depending on the instruction, an extra different EVEX bit field is used to extend the specifier size to 32 registers.

EVEX.U 768 Class field (EVEX byte 2, bit [2]-U)—If EVEX.U=0, it indicates class A or EVEX.U0; if EVEX.U=1, it indicates class B or EVEX.U1.

Prefix encoding field 825 (EVEX byte 2, bits [1:0]-pp)—provides additional bits for the base operation field. In addition to providing support for the legacy SSE instructions in the EVEX prefix format, this also has the benefit of compacting the SIMD prefix (rather than requiring a byte to express the SIMD prefix, the EVEX prefix requires only 2 bits). In one embodiment, to support legacy SSE instructions that use a SIMD prefix (66H, F2H, F3H) in both the legacy format and in the EVEX prefix format, these legacy SIMD prefixes are encoded into the SIMD prefix encoding field; and at runtime are expanded into the legacy SIMD prefix prior to being provided to the decode circuit's PLA (so the PLA can execute both the legacy and EVEX format of these legacy instructions without modification). Although newer instructions could use the EVEX prefix encoding field's content directly as an opcode extension, certain embodiments expand in a similar fashion for consistency but allow for different meanings to be specified by these legacy SIMD prefixes. An alternative embodiment may redesign the PLA to support the 2 bit SIMD prefix encodings, and thus not require the expansion.

Alpha field 752 (EVEX byte 3, bit [7]—EH; also known as EVEX.EH, EVEX.rs, EVEX.RL, EVEX.write mask control, and EVEX.N; also illustrated with α)—as previously described, this field is context specific.

Beta field 754 (EVEX byte 3, bits [6:4]-SSS, also known as EVEX.s₂₋₀, EVEX.r₂₋₀, EVEX.rr1, EVEX.LL0, EVEX.LLB; also illustrated with βββ)—as previously described, this field is context specific.

REX′ field 710—this is the remainder of the REX′ field and is the EVEX.V′ bit field (EVEX Byte 3, bit [3]—V′) that may be used to encode either the upper 16 or lower 16 of the extended 32 register set. This bit is stored in bit inverted format. A value of 1 is used to encode the lower 16 registers. In other words, V′VVVV is formed by combining EVEX.V′, EVEX.vvvv.

Write mask field 770 (EVEX byte 3, bits [2:0]-kkk)—its content specifies the index of a register in the write mask registers as previously described. In one embodiment of the disclosure, the specific value EVEX kkk=000 has a special behavior implying no write mask is used for the particular instruction (this may be implemented in a variety of ways including the use of a write mask hardwired to all ones or hardware that bypasses the masking hardware).

Real Opcode Field 830 (Byte 4) is also known as the opcode byte. Part of the opcode is specified in this field.

MOD R/M Field 840 (Byte 5) includes MOD field 842, Reg field 844, and R/M field 846. As previously described, the MOD field's 842 content distinguishes between memory access and non-memory access operations. The role of Reg field 844 can be summarized to two situations: encoding either the destination register operand or a source register operand, or be treated as an opcode extension and not used to encode any instruction operand. The role of R/M field 846 may include the following: encoding the instruction operand that references a memory address, or encoding either the destination register operand or a source register operand.

Scale, Index, Base (SIB) Byte (Byte 6)—As previously described, the scale field's 750 content is used for memory address generation. SIB.xxx 854 and SIB.bbb 856—the contents of these fields have been previously referred to with regard to the register indexes Xxxx and Bbbb.

Displacement field 762A (Bytes 7-10)—when MOD field 842 contains 10, bytes 7-10 are the displacement field 762A, and it works the same as the legacy 32-bit displacement (disp32) and works at byte granularity.

Displacement factor field 762B (Byte 7)—when MOD field 842 contains 01, byte 7 is the displacement factor field 762B. The location of this field is that same as that of the legacy x86 instruction set 8-bit displacement (disp8), which works at byte granularity. Since disp8 is sign extended, it can only address between −128 and 127 bytes offsets; in terms of 64 byte cache lines, disp8 uses 8 bits that can be set to only four really useful values −128, −64, 0, and 64; since a greater range is often needed, disp32 is used; however, disp32 requires 4 bytes. In contrast to disp8 and disp32, the displacement factor field 762B is a reinterpretation of disp8; when using displacement factor field 762B, the actual displacement is determined by the content of the displacement factor field multiplied by the size of the memory operand access (N). This type of displacement is referred to as disp8*N. This reduces the average instruction length (a single byte of used for the displacement but with a much greater range). Such compressed displacement is based on the assumption that the effective displacement is multiple of the granularity of the memory access, and hence, the redundant low-order bits of the address offset do not need to be encoded. In other words, the displacement factor field 762B substitutes the legacy x86 instruction set 8-bit displacement. Thus, the displacement factor field 762B is encoded the same way as an x86 instruction set 8-bit displacement (so no changes in the ModRM/SIB encoding rules) with the only exception that disp8 is overloaded to disp8*N. In other words, there are no changes in the encoding rules or encoding lengths but only in the interpretation of the displacement value by hardware (which needs to scale the displacement by the size of the memory operand to obtain a byte-wise address offset). Immediate field 772 operates as previously described.

Full Opcode Field

FIG. 8B is a block diagram illustrating the fields of the specific vector friendly instruction format 800 that make up the full opcode field 774 according to one embodiment of the disclosure. Specifically, the full opcode field 774 includes the format field 740, the base operation field 742, and the data element width (W) field 764. The base operation field 742 includes the prefix encoding field 825, the opcode map field 815, and the real opcode field 830.

Register Index Field

FIG. 8C is a block diagram illustrating the fields of the specific vector friendly instruction format 800 that make up the register index field 744 according to one embodiment of the disclosure. Specifically, the register index field 744 includes the REX field 805, the REX′ field 810, the MODR/M.reg field 844, the MODR/M.r/m field 846, the VVVV field 820, xxx field 854, and the bbb field 856.

Augmentation Operation Field

FIG. 8D is a block diagram illustrating the fields of the specific vector friendly instruction format 800 that make up the augmentation operation field 750 according to one embodiment of the disclosure. When the class (U) field 768 contains 0, it signifies EVEX.U0 (class A 768A); when it contains 1, it signifies EVEX.U1 (class B 768B). When U=0 and the MOD field 842 contains 11 (signifying a no memory access operation), the alpha field 752 (EVEX byte 3, bit [7]—EH) is interpreted as the rs field 752A. When the rs field 752A contains a 1 (round 752A.1), the beta field 754 (EVEX byte 3, bits [6:4]—SSS) is interpreted as the round control field 754A. The round control field 754A includes a one bit SAE field 756 and a two bit round operation field 758. When the rs field 752A contains a 0 (data transform 752A.2), the beta field 754 (EVEX byte 3, bits [6:4]—SSS) is interpreted as a three bit data transform field 754B. When U=0 and the MOD field 842 contains 00, 01, or 10 (signifying a memory access operation), the alpha field 752 (EVEX byte 3, bit [7]—EH) is interpreted as the eviction hint (EH) field 752B and the beta field 754 (EVEX byte 3, bits [6:4]—SSS) is interpreted as a three bit data manipulation field 754C.

When U=1, the alpha field 752 (EVEX byte 3, bit [7]—EH) is interpreted as the write mask control (Z) field 752C. When U=1 and the MOD field 842 contains 11 (signifying a no memory access operation), part of the beta field 754 (EVEX byte 3, bit [4]—S₀) is interpreted as the RL field 757A; when it contains a 1 (round 757A.1) the rest of the beta field 754 (EVEX byte 3, bit [6-5]—S₂₋₁) is interpreted as the round operation field 759A, while when the RL field 757A contains a 0 (VSIZE 757.A2) the rest of the beta field 754 (EVEX byte 3, bit [6-5]—S₂₋₁) is interpreted as the vector length field 759B (EVEX byte 3, bit [6-5]—L₁₋₀). When U=1 and the MOD field 842 contains 00, 01, or 10 (signifying a memory access operation), the beta field 754 (EVEX byte 3, bits [6:4]—SSS) is interpreted as the vector length field 759B (EVEX byte 3, bit [6-5]—L₁₋₀) and the broadcast field 757B (EVEX byte 3, bit [4]—B).

Exemplary Register Architecture

FIG. 9 is a block diagram of a register architecture 900 according to one embodiment of the disclosure. In the embodiment illustrated, there are 32 vector registers 910 that are 512 bits wide; these registers are referenced as zmm0 through zmm31. The lower order 256 bits of the lower 16 zmm registers are overlaid on registers ymm0-16. The lower order 128 bits of the lower 16 zmm registers (the lower order 128 bits of the ymm registers) are overlaid on registers xmm0-15. The specific vector friendly instruction format 800 operates on these overlaid register file as illustrated in the below tables.

Adjustable Vector Length Class Operations Registers Instruction Templates A (FIG. 710, 715, zmm registers (the vector length is 64 that do not include the 7A; U = 0) 725, 730 byte) vector length field 759B B (FIG. 712 zmm registers (the vector length is 64 7B; U = 1) byte) Instruction templates that B (FIG. 717, 727 zmm, ymm, or xmm registers (the do include the vector 7B; U = 1) vector length is 64 byte, 32 byte, or 16 length field 759B byte) depending on the vector length field 759B

In other words, the vector length field 759B selects between a maximum length and one or more other shorter lengths, where each such shorter length is half the length of the preceding length; and instructions templates without the vector length field 759B operate on the maximum vector length. Further, in one embodiment, the class B instruction templates of the specific vector friendly instruction format 800 operate on packed or scalar single/double-precision floating point data and packed or scalar integer data. Scalar operations are operations performed on the lowest order data element position in an zmm/ymm/xmm register; the higher order data element positions are either left the same as they were prior to the instruction or zeroed depending on the embodiment.

Write mask registers 915—in the embodiment illustrated, there are 8 write mask registers (k0 through k7), each 64 bits in size. In an alternate embodiment, the write mask registers 915 are 16 bits in size. As previously described, in one embodiment of the disclosure, the vector mask register k0 cannot be used as a write mask; when the encoding that would normally indicate k0 is used for a write mask, it selects a hardwired write mask of 0xFFFF, effectively disabling write masking for that instruction.

General-purpose registers 925—in the embodiment illustrated, there are sixteen 64-bit general-purpose registers that are used along with the existing x86 addressing modes to address memory operands. These registers are referenced by the names RAX, RBX, RCX, RDX, RBP, RSI, RDI, RSP, and R8 through R15.

Scalar floating point stack register file (x87 stack) 945, on which is aliased the MMX packed integer flat register file 950—in the embodiment illustrated, the x87 stack is an eight-element stack used to perform scalar floating-point operations on 32/64/80-bit floating point data using the x87 instruction set extension; while the MMX registers are used to perform operations on 64-bit packed integer data, as well as to hold operands for some operations performed between the MMX and XMM registers.

Alternative embodiments of the disclosure may use wider or narrower registers. Additionally, alternative embodiments of the disclosure may use more, less, or different register files and registers.

Exemplary Core Architectures, Processors, and Computer Architectures

Processor cores may be implemented in different ways, for different purposes, and in different processors. For instance, implementations of such cores may include: 1) a general purpose in-order core intended for general-purpose computing; 2) a high performance general purpose out-of-order core intended for general-purpose computing; 3) a special purpose core intended primarily for graphics and/or scientific (throughput) computing. Implementations of different processors may include: 1) a CPU including one or more general purpose in-order cores intended for general-purpose computing and/or one or more general purpose out-of-order cores intended for general-purpose computing; and 2) a coprocessor including one or more special purpose cores intended primarily for graphics and/or scientific (throughput). Such different processors lead to different computer system architectures, which may include: 1) the coprocessor on a separate chip from the CPU; 2) the coprocessor on a separate die in the same package as a CPU; 3) the coprocessor on the same die as a CPU (in which case, such a coprocessor is sometimes referred to as special purpose logic, such as integrated graphics and/or scientific (throughput) logic, or as special purpose cores); and 4) a system on a chip that may include on the same die the described CPU (sometimes referred to as the application core(s) or application processor(s)), the above described coprocessor, and additional functionality. Exemplary core architectures are described next, followed by descriptions of exemplary processors and computer architectures.

Exemplary Core Architectures In-Order and Out-of-Order Core Block Diagram

FIG. 10A is a block diagram illustrating both an exemplary in-order pipeline and an exemplary register renaming, out-of-order issue/execution pipeline according to embodiments of the disclosure. FIG. 10B is a block diagram illustrating both an exemplary embodiment of an in-order architecture core and an exemplary register renaming, out-of-order issue/execution architecture core to be included in a processor according to embodiments of the disclosure. The solid lined boxes in FIGS. 10A-B illustrate the in-order pipeline and in-order core, while the optional addition of the dashed lined boxes illustrates the register renaming, out-of-order issue/execution pipeline and core. Given that the in-order aspect is a subset of the out-of-order aspect, the out-of-order aspect will be described.

In FIG. 10A, a processor pipeline 1000 includes a fetch stage 1002, a length decode stage 1004, a decode stage 1006, an allocation stage 1008, a renaming stage 1010, a scheduling (also known as a dispatch or issue) stage 1012, a register read/memory read stage 1014, an execute stage 1016, a write back/memory write stage 1018, an exception handling stage 1022, and a commit stage 1024.

FIG. 10B shows processor core 1090 including a front end unit 1030 coupled to an execution engine unit 1050, and both are coupled to a memory unit 1070. The core 1090 may be a reduced instruction set computing (RISC) core, a complex instruction set computing (CISC) core, a very long instruction word (VLIW) core, or a hybrid or alternative core type. As yet another option, the core 1090 may be a special-purpose core, such as, for example, a network or communication core, compression engine, coprocessor core, general purpose computing graphics processing unit (GPGPU) core, graphics core, or the like.

The front end unit 1030 includes a branch prediction unit 1032 coupled to an instruction cache unit 1034, which is coupled to an instruction translation lookaside buffer (TLB) 1036, which is coupled to an instruction fetch unit 1038, which is coupled to a decode unit 1040. The decode unit 1040 (e.g., decode circuit) may decode instructions (e.g., macro-instructions), and generate as an output one or more micro-operations, micro-code entry points, micro-instructions, other instructions, or other control signals, which are decoded from, or which otherwise reflect, or are derived from, the original instructions. The decode unit 1040 may be implemented using various different mechanisms. Examples of suitable mechanisms include, but are not limited to, look-up tables, hardware implementations, programmable logic arrays (PLAs), microcode read only memories (ROMs), etc. In one embodiment, the core 1090 includes a microcode ROM or other medium that stores microcode for certain macro-instructions (e.g., in decode unit 1040 or otherwise within the front end unit 1030). The decode unit 1040 is coupled to a rename/allocator unit 1052 in the execution engine unit 1050.

The execution engine unit 1050 includes the rename/allocator unit 1052 coupled to a retirement unit 1054 and a set of one or more scheduler unit(s) 1056. The scheduler unit(s) 1056 represents any number of different schedulers, including reservations stations, central instruction window, etc. The scheduler unit(s) 1056 is coupled to the physical register file(s) unit(s) 1058. Each of the physical register file(s) units 1058 represents one or more physical register files, different ones of which store one or more different data types, such as scalar integer, scalar floating point, packed integer, packed floating point, vector integer, vector floating point, status (e.g., an instruction pointer that is the address of the next instruction to be executed), etc. In one embodiment, the physical register file(s) unit 1058 comprises a vector registers unit, a write mask registers unit, and a scalar registers unit. These register units may provide architectural vector registers, vector mask registers, and general purpose registers. The physical register file(s) unit(s) 1058 is overlapped by the retirement unit 1054 to illustrate various ways in which register renaming and out-of-order execution may be implemented (e.g., using a reorder buffer(s) and a retirement register file(s); using a future file(s), a history buffer(s), and a retirement register file(s); using a register maps and a pool of registers; etc.). The retirement unit 1054 and the physical register file(s) unit(s) 1058 are coupled to the execution cluster(s) 1060. The execution cluster(s) 1060 includes a set of one or more execution units 1062 (e.g., execution circuits) and a set of one or more memory access units 1064. The execution units 1062 may perform various operations (e.g., shifts, addition, subtraction, multiplication) and on various types of data (e.g., scalar floating point, packed integer, packed floating point, vector integer, vector floating point). While some embodiments may include a number of execution units dedicated to specific functions or sets of functions, other embodiments may include only one execution unit or multiple execution units that all perform all functions. The scheduler unit(s) 1056, physical register file(s) unit(s) 1058, and execution cluster(s) 1060 are shown as being possibly plural because certain embodiments create separate pipelines for certain types of data/operations (e.g., a scalar integer pipeline, a scalar floating point/packed integer/packed floating point/vector integer/vector floating point pipeline, and/or a memory access pipeline that each have their own scheduler unit, physical register file(s) unit, and/or execution cluster—and in the case of a separate memory access pipeline, certain embodiments are implemented in which only the execution cluster of this pipeline has the memory access unit(s) 1064). It should also be understood that where separate pipelines are used, one or more of these pipelines may be out-of-order issue/execution and the rest in-order.

The set of memory access units 1064 is coupled to the memory unit 1070, which includes a data TLB unit 1072 coupled to a data cache unit 1074 coupled to a level 2 (L2) cache unit 1076. In one exemplary embodiment, the memory access units 1064 may include a load unit, a store address unit, and a store data unit, each of which is coupled to the data TLB unit 1072 in the memory unit 1070. The instruction cache unit 1034 is further coupled to a level 2 (L2) cache unit 1076 in the memory unit 1070. The L2 cache unit 1076 is coupled to one or more other levels of cache and eventually to a main memory.

By way of example, the exemplary register renaming, out-of-order issue/execution core architecture may implement the pipeline 1000 as follows: 1) the instruction fetch 1038 performs the fetch and length decoding stages 1002 and 1004; 2) the decode unit 1040 performs the decode stage 1006; 3) the rename/allocator unit 1052 performs the allocation stage 1008 and renaming stage 1010; 4) the scheduler unit(s) 1056 performs the schedule stage 1012; 5) the physical register file(s) unit(s) 1058 and the memory unit 1070 perform the register read/memory read stage 1014; the execution cluster 1060 perform the execute stage 1016; 6) the memory unit 1070 and the physical register file(s) unit(s) 1058 perform the write back/memory write stage 1018; 7) various units may be involved in the exception handling stage 1022; and 8) the retirement unit 1054 and the physical register file(s) unit(s) 1058 perform the commit stage 1024.

The core 1090 may support one or more instructions sets (e.g., the x86 instruction set (with some extensions that have been added with newer versions); the MIPS instruction set of MIPS Technologies of Sunnyvale, Calif.; the ARM instruction set (with optional additional extensions such as NEON) of ARM Holdings of Sunnyvale, Calif.), including the instruction(s) described herein. In one embodiment, the core 1090 includes logic to support a packed data instruction set extension (e.g., AVX1, AVX2), thereby allowing the operations used by many multimedia applications to be performed using packed data.

It should be understood that the core may support multithreading (executing two or more parallel sets of operations or threads), and may do so in a variety of ways including time sliced multithreading, simultaneous multithreading (where a single physical core provides a logical core for each of the threads that physical core is simultaneously multithreading), or a combination thereof (e.g., time sliced fetching and decoding and simultaneous multithreading thereafter such as in the Intel® Hyper-Threading technology).

While register renaming is described in the context of out-of-order execution, it should be understood that register renaming may be used in an in-order architecture. While the illustrated embodiment of the processor also includes separate instruction and data cache units 1034/1074 and a shared L2 cache unit 1076, alternative embodiments may have a single internal cache for both instructions and data, such as, for example, a Level 1 (L1) internal cache, or multiple levels of internal cache. In some embodiments, the system may include a combination of an internal cache and an external cache that is external to the core and/or the processor. Alternatively, all of the cache may be external to the core and/or the processor.

Specific Exemplary In-Order Core Architecture

FIGS. 11A-B illustrate a block diagram of a more specific exemplary in-order core architecture, which core would be one of several logic blocks (including other cores of the same type and/or different types) in a chip. The logic blocks communicate through a high-bandwidth interconnect network (e.g., a ring network) with some fixed function logic, memory I/O interfaces, and other necessary I/O logic, depending on the application.

FIG. 11A is a block diagram of a single processor core, along with its connection to the on-die interconnect network 1102 and with its local subset of the Level 2 (L2) cache 1104, according to embodiments of the disclosure. In one embodiment, an instruction decode unit 1100 supports the x86 instruction set with a packed data instruction set extension. An L1 cache 1106 allows low-latency accesses to cache memory into the scalar and vector units. While in one embodiment (to simplify the design), a scalar unit 1108 and a vector unit 1110 use separate register sets (respectively, scalar registers 1112 and vector registers 1114) and data transferred between them is written to memory and then read back in from a level 1 (L1) cache 1106, alternative embodiments of the disclosure may use a different approach (e.g., use a single register set or include a communication path that allow data to be transferred between the two register files without being written and read back).

The local subset of the L2 cache 1104 is part of a global L2 cache that is divided into separate local subsets, one per processor core. Each processor core has a direct access path to its own local subset of the L2 cache 1104. Data read by a processor core is stored in its L2 cache subset 1104 and can be accessed quickly, in parallel with other processor cores accessing their own local L2 cache subsets. Data written by a processor core is stored in its own L2 cache subset 1104 and is flushed from other subsets, if necessary. The ring network ensures coherency for shared data. The ring network is bi-directional to allow agents such as processor cores, L2 caches and other logic blocks to communicate with each other within the chip. Each ring data-path is 1012-bits wide per direction.

FIG. 11B is an expanded view of part of the processor core in FIG. 11A according to embodiments of the disclosure. FIG. 11B includes an L1 data cache 1106A part of the L1 cache 1104, as well as more detail regarding the vector unit 1110 and the vector registers 1114. Specifically, the vector unit 1110 is a 16-wide vector processing unit (VPU) (see the 16-wide ALU 1128), which executes one or more of integer, single-precision float, and double-precision float instructions. The VPU supports swizzling the register inputs with swizzle unit 1120, numeric conversion with numeric convert units 1122A-B, and replication with replication unit 1124 on the memory input. Write mask registers 1126 allow predicating resulting vector writes.

FIG. 12 is a block diagram of a processor 1200 that may have more than one core, may have an integrated memory controller, and may have integrated graphics according to embodiments of the disclosure. The solid lined boxes in FIG. 12 illustrate a processor 1200 with a single core 1202A, a system agent 1210, a set of one or more bus controller units 1216, while the optional addition of the dashed lined boxes illustrates an alternative processor 1200 with multiple cores 1202A-N, a set of one or more integrated memory controller unit(s) 1214 in the system agent unit 1210, and special purpose logic 1208.

Thus, different implementations of the processor 1200 may include: 1) a CPU with the special purpose logic 1208 being integrated graphics and/or scientific (throughput) logic (which may include one or more cores), and the cores 1202A-N being one or more general purpose cores (e.g., general purpose in-order cores, general purpose out-of-order cores, a combination of the two); 2) a coprocessor with the cores 1202A-N being a large number of special purpose cores intended primarily for graphics and/or scientific (throughput); and 3) a coprocessor with the cores 1202A-N being a large number of general purpose in-order cores. Thus, the processor 1200 may be a general-purpose processor, coprocessor or special-purpose processor, such as, for example, a network or communication processor, compression engine, graphics processor, GPGPU (general purpose graphics processing unit), a high-throughput many integrated core (MIC) coprocessor (including 30 or more cores), embedded processor, or the like. The processor may be implemented on one or more chips. The processor 1200 may be a part of and/or may be implemented on one or more substrates using any of a number of process technologies, such as, for example, BiCMOS, CMOS, or NMOS.

The memory hierarchy includes one or more levels of cache within the cores, a set or one or more shared cache units 1206, and external memory (not shown) coupled to the set of integrated memory controller units 1214. The set of shared cache units 1206 may include one or more mid-level caches, such as level 2 (L2), level 3 (L3), level 4 (L4), or other levels of cache, a last level cache (LLC), and/or combinations thereof. While in one embodiment a ring based interconnect unit 1212 interconnects the integrated graphics logic 1208, the set of shared cache units 1206, and the system agent unit 1210/integrated memory controller unit(s) 1214, alternative embodiments may use any number of well-known techniques for interconnecting such units. In one embodiment, coherency is maintained between one or more cache units 1206 and cores 1202-A-N.

In some embodiments, one or more of the cores 1202A-N are capable of multi-threading. The system agent 1210 includes those components coordinating and operating cores 1202A-N. The system agent unit 1210 may include for example a power control unit (PCU) and a display unit. The PCU may be or include logic and components needed for regulating the power state of the cores 1202A-N and the integrated graphics logic 1208. The display unit is for driving one or more externally connected displays.

The cores 1202A-N may be homogenous or heterogeneous in terms of architecture instruction set; that is, two or more of the cores 1202A-N may be capable of execution the same instruction set, while others may be capable of executing only a subset of that instruction set or a different instruction set.

Exemplary Computer Architectures

FIGS. 13-16 are block diagrams of exemplary computer architectures. Other system designs and configurations known in the arts for laptops, desktops, handheld PCs, personal digital assistants, engineering workstations, servers, network devices, network hubs, switches, embedded processors, digital signal processors (DSPs), graphics devices, video game devices, set-top boxes, micro controllers, cell phones, portable media players, hand held devices, and various other electronic devices, are also suitable. In general, a huge variety of systems or electronic devices capable of incorporating a processor and/or other execution logic as disclosed herein are generally suitable.

Referring now to FIG. 13, shown is a block diagram of a system 1300 in accordance with one embodiment of the present disclosure. The system 1300 may include one or more processors 1310, 1315, which are coupled to a controller hub 1320. In one embodiment the controller hub 1320 includes a graphics memory controller hub (GMCH) 1390 and an Input/Output Hub (IOH) 1350 (which may be on separate chips); the GMCH 1390 includes memory and graphics controllers to which are coupled memory 1340 and a coprocessor 1345; the IOH 1350 is couples input/output (I/O) devices 1360 to the GMCH 1390. Alternatively, one or both of the memory and graphics controllers are integrated within the processor (as described herein), the memory 1340 and the coprocessor 1345 are coupled directly to the processor 1310, and the controller hub 1320 in a single chip with the IOH 1350. Memory 1340 may include data request servicing code 1340A, for example, to store code that when executed causes a processor to perform any method of this disclosure.

The optional nature of additional processors 1315 is denoted in FIG. 13 with broken lines. Each processor 1310, 1315 may include one or more of the processing cores described herein and may be some version of the processor 1200.

The memory 1340 may be, for example, dynamic random access memory (DRAM), phase change memory (PCM), or a combination of the two. For at least one embodiment, the controller hub 1320 communicates with the processor(s) 1310, 1315 via a multi-drop bus, such as a frontside bus (FSB), point-to-point interface such as Quickpath Interconnect (QPI), or similar connection 1395.

In one embodiment, the coprocessor 1345 is a special-purpose processor, such as, for example, a high-throughput MIC processor, a network or communication processor, compression engine, graphics processor, GPGPU, embedded processor, or the like. In one embodiment, controller hub 1320 may include an integrated graphics accelerator.

There can be a variety of differences between the physical resources 1310, 1315 in terms of a spectrum of metrics of merit including architectural, microarchitectural, thermal, power consumption characteristics, and the like.

In one embodiment, the processor 1310 executes instructions that control data processing operations of a general type. Embedded within the instructions may be coprocessor instructions. The processor 1310 recognizes these coprocessor instructions as being of a type that should be executed by the attached coprocessor 1345. Accordingly, the processor 1310 issues these coprocessor instructions (or control signals representing coprocessor instructions) on a coprocessor bus or other interconnect, to coprocessor 1345. Coprocessor(s) 1345 accept and execute the received coprocessor instructions.

Referring now to FIG. 14, shown is a block diagram of a first more specific exemplary system 1400 in accordance with an embodiment of the present disclosure. As shown in FIG. 14, multiprocessor system 1400 is a point-to-point interconnect system, and includes a first processor 1470 and a second processor 1480 coupled via a point-to-point interconnect 1450. Each of processors 1470 and 1480 may be some version of the processor 1200. In one embodiment of the disclosure, processors 1470 and 1480 are respectively processors 1310 and 1315, while coprocessor 1438 is coprocessor 1345. In another embodiment, processors 1470 and 1480 are respectively processor 1310 coprocessor 1345.

Processors 1470 and 1480 are shown including integrated memory controller (IMC) units 1472 and 1482, respectively. Processor 1470 also includes as part of its bus controller units point-to-point (P-P) interfaces 1476 and 1478; similarly, second processor 1480 includes P-P interfaces 1486 and 1488. Processors 1470, 1480 may exchange information via a point-to-point (P-P) interface 1450 using P-P interface circuits 1478, 1488. As shown in FIG. 14, IMCs 1472 and 1482 couple the processors to respective memories, namely a memory 1432 and a memory 1434, which may be portions of main memory locally attached to the respective processors.

Processors 1470, 1480 may each exchange information with a chipset 1490 via individual P-P interfaces 1452, 1454 using point to point interface circuits 1476, 1494, 1486, 1498. Chipset 1490 may optionally exchange information with the coprocessor 1438 via a high-performance interface 1439. In one embodiment, the coprocessor 1438 is a special-purpose processor, such as, for example, a high-throughput MIC processor, a network or communication processor, compression engine, graphics processor, GPGPU, embedded processor, or the like.

A shared cache (not shown) may be included in either processor or outside of both processors, yet connected with the processors via P-P interconnect, such that either or both processors' local cache information may be stored in the shared cache if a processor is placed into a low power mode.

Chipset 1490 may be coupled to a first bus 1416 via an interface 1496. In one embodiment, first bus 1416 may be a Peripheral Component Interconnect (PCI) bus, or a bus such as a PCI Express bus or another third generation I/O interconnect bus, although the scope of the present disclosure is not so limited.

As shown in FIG. 14, various I/O devices 1414 may be coupled to first bus 1416, along with a bus bridge 1418 which couples first bus 1416 to a second bus 1420. In one embodiment, one or more additional processor(s) 1415, such as coprocessors, high-throughput MIC processors, GPGPU's, accelerators (such as, e.g., graphics accelerators or digital signal processing (DSP) units), field programmable gate arrays, or any other processor, are coupled to first bus 1416. In one embodiment, second bus 1420 may be a low pin count (LPC) bus. Various devices may be coupled to a second bus 1420 including, for example, a keyboard and/or mouse 1422, communication devices 1427 and a storage unit 1428 such as a disk drive or other mass storage device which may include instructions/code and data 1430, in one embodiment. Further, an audio I/O 1424 may be coupled to the second bus 1420. Note that other architectures are possible. For example, instead of the point-to-point architecture of FIG. 14, a system may implement a multi-drop bus or other such architecture.

Referring now to FIG. 15, shown is a block diagram of a second more specific exemplary system 1500 in accordance with an embodiment of the present disclosure. Like elements in FIGS. 14 and 15 bear like reference numerals, and certain aspects of FIG. 14 have been omitted from FIG. 15 in order to avoid obscuring other aspects of FIG. 15.

FIG. 15 illustrates that the processors 1470, 1480 may include integrated memory and I/O control logic (“CL”) 1472 and 1482, respectively. Thus, the CL 1472, 1482 include integrated memory controller units and include I/O control logic. FIG. 15 illustrates that not only are the memories 1432, 1434 coupled to the CL 1472, 1482, but also that I/O devices 1514 are also coupled to the control logic 1472, 1482. Legacy I/O devices 1515 are coupled to the chipset 1490.

Referring now to FIG. 16, shown is a block diagram of a SoC 1600 in accordance with an embodiment of the present disclosure. Similar elements in FIG. 12 bear like reference numerals. Also, dashed lined boxes are optional features on more advanced SoCs. In FIG. 16, an interconnect unit(s) 1602 is coupled to: an application processor 1610 which includes a set of one or more cores 202A-N and shared cache unit(s) 1206; a system agent unit 1210; a bus controller unit(s) 1216; an integrated memory controller unit(s) 1214; a set or one or more coprocessors 1620 which may include integrated graphics logic, an image processor, an audio processor, and a video processor; an static random access memory (SRAM) unit 1630; a direct memory access (DMA) unit 1632; and a display unit 1640 for coupling to one or more external displays. In one embodiment, the coprocessor(s) 1620 include a special-purpose processor, such as, for example, a network or communication processor, compression engine, GPGPU, a high-throughput MIC processor, embedded processor, or the like.

Embodiments (e.g., of the mechanisms) disclosed herein may be implemented in hardware, software, firmware, or a combination of such implementation approaches. Embodiments of the disclosure may be implemented as computer programs or program code executing on programmable systems comprising at least one processor, a storage system (including volatile and non-volatile memory and/or storage elements), at least one input device, and at least one output device.

Program code, such as code 1430 illustrated in FIG. 14, may be applied to input instructions to perform the functions described herein and generate output information. The output information may be applied to one or more output devices, in known fashion. For purposes of this application, a processing system includes any system that has a processor, such as, for example; a digital signal processor (DSP), a microcontroller, an application specific integrated circuit (ASIC), or a microprocessor.

The program code may be implemented in a high level procedural or object oriented programming language to communicate with a processing system. The program code may also be implemented in assembly or machine language, if desired. In fact, the mechanisms described herein are not limited in scope to any particular programming language. In any case, the language may be a compiled or interpreted language.

One or more aspects of at least one embodiment may be implemented by representative instructions stored on a machine-readable medium which represents various logic within the processor, which when read by a machine causes the machine to fabricate logic to perform the techniques described herein. Such representations, known as “IP cores” may be stored on a tangible, machine readable medium and supplied to various customers or manufacturing facilities to load into the fabrication machines that actually make the logic or processor.

Such machine-readable storage media may include, without limitation, non-transitory, tangible arrangements of articles manufactured or formed by a machine or device, including storage media such as hard disks, any other type of disk including floppy disks, optical disks, compact disk read-only memories (CD-ROMs), compact disk rewritable's (CD-RWs), and magneto-optical disks, semiconductor devices such as read-only memories (ROMs), random access memories (RAMs) such as dynamic random access memories (DRAMs), static random access memories (SRAMs), erasable programmable read-only memories (EPROMs), flash memories, electrically erasable programmable read-only memories (EEPROMs), phase change memory (PCM), magnetic or optical cards, or any other type of media suitable for storing electronic instructions.

Accordingly, embodiments of the disclosure also include non-transitory, tangible machine-readable media containing instructions or containing design data, such as Hardware Description Language (HDL), which defines structures, circuits, apparatuses, processors and/or system features described herein. Such embodiments may also be referred to as program products.

Emulation (including Binary Translation, Code Morphing, etc.)

In some cases, an instruction converter may be used to convert an instruction from a source instruction set to a target instruction set. For example, the instruction converter may translate (e.g., using static binary translation, dynamic binary translation including dynamic compilation), morph, emulate, or otherwise convert an instruction to one or more other instructions to be processed by the core. The instruction converter may be implemented in software, hardware, firmware, or a combination thereof. The instruction converter may be on processor, off processor, or part on and part off processor.

FIG. 17 is a block diagram contrasting the use of a software instruction converter to convert binary instructions in a source instruction set to binary instructions in a target instruction set according to embodiments of the disclosure. In the illustrated embodiment, the instruction converter is a software instruction converter, although alternatively the instruction converter may be implemented in software, firmware, hardware, or various combinations thereof. FIG. 17 shows a program in a high level language 1702 may be compiled using an x86 compiler 1704 to generate x86 binary code 1706 that may be natively executed by a processor with at least one x86 instruction set core 1716. The processor with at least one x86 instruction set core 1716 represents any processor that can perform substantially the same functions as an Intel® processor with at least one x86 instruction set core by compatibly executing or otherwise processing (1) a substantial portion of the instruction set of the Intel® x86 instruction set core or (2) object code versions of applications or other software targeted to run on an Intel® processor with at least one x86 instruction set core, in order to achieve substantially the same result as an Intel® processor with at least one x86 instruction set core. The x86 compiler 1704 represents a compiler that is operable to generate x86 binary code 1706 (e.g., object code) that can, with or without additional linkage processing, be executed on the processor with at least one x86 instruction set core 1716. Similarly, FIG. 17 shows the program in the high level language 1702 may be compiled using an alternative instruction set compiler 1708 to generate alternative instruction set binary code 1710 that may be natively executed by a processor without at least one x86 instruction set core 1714 (e.g., a processor with cores that execute the MIPS instruction set of MIPS Technologies of Sunnyvale, Calif. and/or that execute the ARM instruction set of ARM Holdings of Sunnyvale, Calif.). The instruction converter 1712 is used to convert the x86 binary code 1706 into code that may be natively executed by the processor without an x86 instruction set core 1714. This converted code is not likely to be the same as the alternative instruction set binary code 1710 because an instruction converter capable of this is difficult to make; however, the converted code will accomplish the general operation and be made up of instructions from the alternative instruction set. Thus, the instruction converter 1712 represents software, firmware, hardware, or a combination thereof that, through emulation, simulation or any other process, allows a processor or other electronic device that does not have an x86 instruction set processor or core to execute the x86 binary code 1706. 

What is claimed is:
 1. A processor comprising: a decode circuit to decode instructions into decoded instructions; an execution circuit to execute the decoded instructions; and a memory circuit comprising a load data translation lookaside buffer circuit and a store data translation lookaside buffer circuit separate and distinct from the load data translation lookaside buffer circuit, wherein the memory circuit sends a memory access request of the instructions to the load data translation lookaside buffer circuit when the memory access request is a load data request and to the store data translation lookaside buffer circuit when the memory access request is a store data request to determine a physical address for a virtual address of the memory access request, and the load data translation lookaside buffer circuit and the store data translation lookaside buffer circuit are different sizes and different associativity.
 2. The processor of claim 1, wherein the load data translation lookaside buffer circuit comprises more entry storage locations than the store data translation lookaside buffer circuit.
 3. The processor of claim 1, wherein the load data translation lookaside buffer circuit is updated on each load operation and each store operation of the instructions.
 4. The processor of claim 3, wherein the store data translation lookaside buffer circuit is updated only by each store operation of the instructions.
 5. The processor of claim 1, wherein the store data translation lookaside buffer circuit is updated independently of the load data translation lookaside buffer circuit.
 6. The processor of claim 1, wherein the store data translation lookaside buffer circuit is updated only by each store operation of the instructions.
 7. The processor of claim 1, wherein the load data request is to be input into one of a plurality of load ports of the load data translation lookaside buffer circuit.
 8. The processor of claim 1, wherein the store data request is to be input into one of a plurality of store ports of the store data translation lookaside buffer circuit.
 9. A method comprising: receiving a memory access request of an instruction from a processor with a memory circuit; determining, by the memory circuit, when the memory access request is a load data request or a store data request; sending the memory access request to a load data translation lookaside buffer circuit when the memory access request is the load data request and to a store data translation lookaside buffer circuit separate and distinct from the load data translation lookaside buffer circuit when the memory access request is the store data request to determine a physical address for a virtual address of the memory access request, wherein the load data translation lookaside buffer circuit and the store data translation lookaside buffer circuit are different sizes and different associativity; and performing a memory access for the memory access request at the physical address.
 10. The method of claim 9, wherein the load data translation lookaside buffer circuit comprises more entry storage locations than the store data translation lookaside buffer circuit.
 11. The method of claim 9, further comprising updating the load data translation lookaside buffer circuit on each load operation and each store operation of the instructions.
 12. The method of claim 11, further comprising updating the store data translation lookaside buffer circuit only by each store operation of the instructions.
 13. The method of claim 9, further comprising updating the store data translation lookaside buffer circuit independently of updating the load data translation lookaside buffer circuit.
 14. The method of claim 9, further comprising updating the store data translation lookaside buffer circuit only by each store operation of the instructions.
 15. The method of claim 9, wherein the sending the memory access request comprises inputting the load data request into one of a plurality of load ports of the load data translation lookaside buffer circuit.
 16. The method of claim 9, wherein the sending the memory access request comprises inputting the store data request into one of a plurality of store ports of the store data translation lookaside buffer circuit.
 17. A system comprising: a processor core comprising: a decode circuit to decode instructions into decoded instructions, and an execution circuit to execute the decoded instructions; and a memory circuit coupled to the processor core and comprising a load data translation lookaside buffer circuit and a store data translation lookaside buffer circuit separate and distinct from the load data translation lookaside buffer circuit, wherein the memory circuit sends a memory access request of the instructions to the load data translation lookaside buffer circuit when the memory access request is a load data request and to the store data translation lookaside buffer circuit when the memory access request is a store data request to determine a physical address for a virtual address of the memory access request, and the load data translation lookaside buffer circuit and the store data translation lookaside buffer circuit are different sizes and different associativity.
 18. The system of claim 17, wherein the load data translation lookaside buffer circuit comprises more entry storage locations than the store data translation lookaside buffer circuit.
 19. The system of claim 17, wherein the load data translation lookaside buffer circuit is updated on each load operation and each store operation of the instructions.
 20. The system of claim 19, wherein the store data translation lookaside buffer circuit is updated only by each store operation of the instructions.
 21. The system of claim 17, wherein the store data translation lookaside buffer circuit is updated independently of the load data translation lookaside buffer circuit.
 22. The system of claim 17, wherein the store data translation lookaside buffer circuit is updated only by each store operation of the instructions.
 23. The system of claim 17, wherein the load data request is to be input into one of a plurality of load ports of the load data translation lookaside buffer circuit.
 24. The system of claim 17, wherein the store data request is to be input into one of a plurality of store ports of the store data translation lookaside buffer circuit. 